Thursday, March 25, 2010

The clip above is short and sweet, with some very cool images. The one below is notable for its shameless fear mongering... unsurprising I guess, given the channel. I'm not going to bother doing a point-by-point analysis of where risks and dangers are exaggerated and overstated, but I'm irritated by the repeated implication that explosive volcanism is the concern here. There could be locally devastating steam explosions, as basaltic lava (at 1100-1200 C) interacts with groundwater, surface water, or ice, but we're not talking St. Helens, let alone Long Valley, Yellowstone or Tambora. Rundle doesn't really help clarify the issue either, but I have to give him credit for ending with "We'll be fine."

The next has some of the same footage as The Guardian clip, but I like the editing of that one better.

And one more; this looks like it might be the source for much of the previous one and the clip at the Guardian.

I'm not seeing any evidence that the fissure is extending, so the repeated message that this eruption may "trigger," "cause," or "force" an eruption at Katla, should be taken with a large block of salt. Since they have been on the ground at the site, I'd be willing to bet they've put in more seismometers to better pick out tremors from magma movement and rock fracturing nearby, and better distinguish those signals from noise resulting from the eruption. But this much is clear to me: gas is escaping easily (note the fountains), and the magma/lava is quite fluid. This is not a constipated system. We don't need to worry about an explosive eruption based on current conditions.